Boric acid has been used as a wood preservative for over 60 years for preventive use in water-soluble wood preservatives. Boric acid is particularly suitable as a wood preservative by its action as a feeding poison against insects as well as against bacteria (Aspergilus niger = mold).

Boric acid strengthens the cell walls, increases the rate of photosynthesis and stabilizes the assimilate transport. Boric acid provides a regulated hormone balance for less water evaporation of the leaves for optimal nutrient absorption. A good boron supply optimizes the earnings potential during harvest. Foliar fertilization with boric acid is the most cost-effective and safe way to supply boron to sugar beets, maize, oilseed rape, hops, wine, vegetables and other crops.

Boric acid is used in various glass products. Thus it is used in the production of borosilicate glass as one of the most important applications in the glass industry. The most important properties of borosilicate glass, when used e.g. as a laboratory glass to achieve a high thermal shock resistance. Furthermore, boron compounds are used for the production of insulating fiber glass (IFG) and reinforcing glass fiber (RFG), boron thereby improving the flowability and reduces melting temperatures in the glass batch.

Boric acid is mainly used in the production of low-temperature melting frits. Furthermore, borates also help reduce thermal expansion, favoring a good fit between the glaze and the clay. Borates also increase the refractive index or gloss of the glazes.

Boric acid is used as a fire retardant particularly in cellulose insulation materials or other natural insulating materials (such as hemp), since boron salts, when supplied with energy / heat (ie in case of fire), secrete water which reduces its flammability. On the other hand, boric acid is considered to be a relatively mild fungicide, without leading to a VOC burden. An insecticidal effect has also been demonstrated.